Purifying water for drinking and industrial applications is essential in many areas of the world. Common methods of water purification include carbon filtration, distillation and reverse osmosis. Carbon filtration is cost effective and may be used in passive systems, however its effectiveness at purifying water is limited. Distillation is a powerful method of producing chemically pure water, however it requires significant energy expenditures. Reverse osmosis is also a powerful filtration method, however it requires pressurized water to work properly. Also, there is much waste product.
Therefore, there exists a need for an effective, energy efficient water purification system that can be used in areas of the world where access to electrical power is limited. The present invention is a water filtration and transport system that is powered by solar energy. Its energy efficient design makes it especially useful in isolated areas or in areas where water is in short supply, such as the Southwest United States.
It is one object of the invention to provide a system and method for purifying water using adsorbent. Another object of the invention is to provide a system and method for purifying water utilizing solar energy. It is another object of the invention to provide an adsorbent to purify water. It is yet another object of the invention to provide a system capable of transmitting of water against gravity. It is another object of the invention to provide a system and method of purifying water while minimizing energy expenditures. It is yet another object of the invention to provide a system and method utilizing adsorbent to sublimate ice, yielding 8.5 pounds of ice for every one pound of vapor formed. Stated another way, an object is to provide a system is capable of forming 8.5 pounds of ice for every pound of sublimated ice.
The present invention utilizes two distinct properties of adsorbent. For water purification, the system cyclically heats and cools adsorbent that has adsorbed water vapor. Since adsorbent capacity decreases with increased temperature, pure water may be harvested from the adsorbent after each heating step.
The present invention creates water vapor by sublimation after at least a first molecular layer of ice is formed on a body of water. To create one pound of sublimated vapor at 32 degrees F., 1218.7 btu must be removed from the ice. To freeze one pound of water at 32 degrees F., 143.34 btu must be removed the water. It is calculated that sublimation of one pound of ice yields one pound of pure vapor and 8.5 pounds of pure ice. In the present invention, pure water is harvested from the vapor and ice formed. Therefore, a total of 9.5 pounds of pure water can be harvested for every one pound of sublimated vapor. Since sublimation requires a removal of more heat than evaporation, a conservative calculation uses 7 pounds of ice formed for every one pound of sublimated vapor. In this calculation, each pound of sublimated vapor yields 8 pounds of purified water. Therefore, the present invention is 8 times more energy efficient at purifying water than a conventional distiller that utilizes evaporation and condensation to purify water.
The present invention also utilizes unique properties of adsorbed liquid. It is noted that in adsorbed water behaves much like a gas in that it is compressible and has a tendency to move from areas of greater density to areas of lower density. This property is utilized in a water transportation system comprising a transmission pipe containing adsorbent material. Water introduced to one end of the transmission pipe tends to travel along the length of the pipe, even overcoming the force of gravity. It is theorized that trees and water tables operate by the same principle.
The objective is, by using an adsorbent, 8.5 pounds of ice can be formed by 1 pound of vapor. That is, the sublimation of one pound of ice freezes 8.5 pounds of water. One pound of sublimated vapor at 32 degrees F. requires 1218.7 btu. One pound of water is frozen by removal of 143,34 btu. After the first molecular layer of ice is formed we are dealing with ice not water. Therefore, one pound of vapor is pure and 8.5 pounds of Ice is pure giving a total of 9.5 pounds of pure water when they are combined. Sublimating ice requires more energy than evaporating water requires and it has been found, by demonstration, that typically 7 pounds of ice is formed by one pound of vapor. This reduction in pounds of ice is due to losses in the system which can be reduced. Therefore, there is an 8 times advantage for the same energy over evaporation and condensation. This is the objective of our patent application.